Electrochemical performance of activated screen printed carbon electrodes for hydrogen peroxide and phenol derivatives sensing

Abstract

Screen-printed carbon electrodes (SPCEs) are widely used for the electroanalysis of a plethora of organic and inorganic compounds. These devices offer unique properties to address electroanalytical chemistry challenges and can successfully compete in numerous aspects with conventional carbon-based electrodes. However, heterogeneous kinetics on SPCEs surfaces is comparatively sluggish, which is why the electrochemical activation of inks is sometimes required to improve electron transfer rates and to enhance sensing performance. In this work, SPCEs were subjected to different electrochemical activation methods and the response to H2O2 electroanalysis was used as a testing probe. Changes in topology, surface chemistry and electrochemical behavior to H2O2 oxidation were performed by SEM, XPS, cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy. The combination of electrochemical activation methods using H2SO4 and H2O2 proved particularly effective. A reduction in charge transfer resistance, together with functionalization with some carbon-oxygen groups on carbon ink surfaces, were likely responsible for such electrochemical improvement. The use of a two-step protocol with 0.5 M H2SO4 and 10 mM H2O2 under potential cycling conditions was the most effective activation procedure investigated herein, and gave rise to 518-fold higher sensitivity than that obtained for the untreated SPCEs upon H2O2 electrooxidation. The electrochemical behavior of acetaminophen, hydroquinone and dopamine is also shown, as a proof of concept upon the optimum activated SPCEs.

Glucose Biosensor Based on Disposable Activated Carbon Electrodes Modified with Platinum Nanoparticles Electrodeposited on Poly(Azure A)

“…Figure 1 shows the linear scan voltammetry (LSV) curves for the H2O2 electro-oxidation at the different modification steps of the biosensor, both in the absence and presence of H2O2, namely: SPCE, aSPCE, PAA-aSPCE, PtNPs-PAA-aSPCE, and the final biosensor GOx-PtNPs-PAA-aSPCE. (Figure 2A,B), which is a similar response to that reported in the literature [26]. After the electrodeposition of PAA, the surface displayed a smooth morphology, which confirmed that the aSPCE was coated by the polymeric film ( Figure 2C).…”

<p>An Electrochemical Aptasensor Platform Based on Flower-Like Gold Microstructure-Modified Screen-Printed Carbon Electrode for Detection of Serpin A12 as a Type 2 Diabetes Biomarker</p>

“…Presence of most active sites on the electrode surface and removal of the oxide coating in previous studies demonstrated the significant increase in electrochemical performance. 41,42 The SPCE was characterized by CV (−0.4 to +0.6 V) in a solution of 0.1 M KCl containing 5 mM K 3 [Fe (CN) 6 ]/K 4 [Fe (CN) 6 ] with scan rates of 0.1 V/s, after the activation process. The deposition time of the FLGMs could considerably affect the size, deposition quantity and extent of the Au microstructures on the SPCE.…”

Flexible Carbon Electrodes for Electrochemical Detection of Bisphenol-A, Hydroquinone and Catechol in Water Samples

“…The enhanced sensitivity is attributed to the removal of non-electroactive components such as resins, solvents, and additives from the carbon ink induced by the pretreatment. This increases the electroactive area at the working electrode surface, which leads to a nanostructured film on the electrode-solution interface comprising graphite and carbon nanoparticles (Carbon Black) [30]. SEM images of flexible SPEs were collected to assess if the morphology of SPEs is unaffected by the electrochemical pretreatment.…”